Protection apparatus for dynamo-electric machines.



R; H. MARRIOTT.

PROTECTION APPARATUS FOR DYNAMO ELECTRIC MACHINES. APPLICATION mum NOV. 27. 1909.

Patented Dec. 13, 1910.

" tecting electro-dynamic machinery from'dis-x UNITED STATES PATENT OFFICE- Rosana 1r. MARRIOTT, or BnooKLYn, NEW YORK,1.AS$IGNOR TO UNITED WIRELESS zrnnnenaraoomrnnr, a'conronn'rron or MAlINE.

PROTECTION APPARATUS FOR DYNAMO-ELECTRIC MACHINES of Brooklyn, Kings countyj New York,'have.

invented'certain new and useful Improvements in Protection Ap aratus for Dynamo Electric Machines, of w iich the following is a specification.

,In wireless telegraph stations, it is desirable to insulate theframe, and thus insulate the windings of the dynamo which supplies the charging currentfor thesending antennae, and in case a motor generator is used, it is-also desirable to insulate the frame and windings of the motor of the set. The frame of the motor. and of the enerator, when insulated, has an Iappreciab e capacity in a high frequency circuit. If high frequency oscillations or waves strike the line wlres of the dynamo or motor, (these oscillations orwaves will tend to set up electric, oscillations in a circuit including the leads and the.

frame of the dynamo or motor. The electric oscillations may originate in the aerial, arranged nearthe machine and reach the Inachine through the leads connecting the windlating apparatus. In either ings t0 a re 1 case, they W1 I tend to break down the insulation betweenthe frame and the. wires.

My invention relates tomeans for, proruptive discharges caused by'high frequency -waves, and more particularl my inventionrelates to meansfor, protec ing such ma- 5 chinery from the influences, of electric waves originated by a sending antenna, the charging current for'which'is supplied by the-machine to be protected. 7

One of the objects of inventionis to 4 provide a means for, protecting the insulated frame of a dynamo electric machlne and to prevent disru tive discharges in such a machine, by com i'ning with themachine to be protected a condenser, one terminal of the condenser being connected to the machine frame, and the other to the windings of the machine. Another object of my invention is to dpro vide an easy path between the leads an f the 5 frame of the machine for the high frequency oscillations, this. path'bein'g of such a natiire'f that it will not allow a substantial amount" of the current of the dynamo or 'motorto ass throu hit. P g

Specification of Letters Patent.

1 With the above'and other'objects in View,

Patented Dec. 13, 1910. 27, 1909. Serial No. 580,0;6.

'my invention consists in the parts,- improve-' ments and combinations more fully pointed out hereinafter.

Referringv now to the drawi s attached to this specification, and formm apart thereof:- Figure 1 is a diagrammatic view of a motor generator set, the generator supplying the charging ,current to a local circuit. having anr antenna. a Fig. 2. is a diagram-- matic view, in which in addition to the con-' densers used in Fig.1, aplurality of inductance coils are -used, for the purpose of-pro-' tecting the windings, of the electro-dynamic machine.

The dgnamo :1 is insulated at its base, as. indicate at 2, and isdriven by. amotor The dynamo and-motor usually restv on the same insulated base. Suitable wires 4, 5 run. from the dynamo through theflkey 6' and thropgh the primary circuit 7 of a transformer, whose secondary is indicated atv 8. The secondary of the transformer is con- .nected to a local closed bscillatorycircuit of a wireless t'ele raph transmitter, which cir-- spark to pass through the s ark a 10. This charges the antenna 11, :vhich h s an inductance 12" inserted .therein' for tuning purposes. V v

In accordance with my invention, I pro- .vide a plurality of 'c'ondensers 13, 14, one coating of'each condenserbeing connected to 'the frame 15 of the generator 1 by a wire 16. Each of the, other coatings of the condensers 13,114 are connected respectively to the wires f lpand 5, as indicated. By' this means any high. frequency waves ,or oscillations caused by'the antenna circuit 11 sending out waves whichare collected by the wires i and-"5, .or by any other." action, are prevented from passing through. the insulation of the wind? ing sin the dynamo 1 to the frame 15 through the wiresi iand. Instead 'of doing th1s, .they pass through the condensers 13 and 14 to theframe 15, and the oscillations die down "in the condenser circ uit where they. are a sorbed. In accordance with my;invention,I correspondingly protect the motor 3 by cong necting one coatln ofa plurality of-tcondensers17, 18,19, Ojto the frame 21 of the 'motor 3, whichframeislikewise insulated, and" by connecting the other coatings of. the

condensers by wires 22, 23,24, 25eto thelead ,irlilg-in wires 26 and 27 supplying current to cuit contains t'e condenser 9, and causes a. 80

e motor, and to'th'e wires 28, 29"connecting the starting rheostat 80 mounted on switchboard with the motor.

Referring now to Fig. 2, the motor 3 with i nsulated frame 2-1 is of the usual compound type, having a shunt winding 31, and a series winding 32. One coating of the con= densers 17, l8, l9 and 20 is connected to the leading-in wires 26, 27, which supply the current, and to the wires 28, 29, which connect the starting rheostat 30 with the'motor.

The other coating .of the condensers 17, 18, 19 and 20 is connected to the frame of the machine by'wire 33. The starting rheostat 30 is arran ed in series with the fields as usual. A p urality of inductances 34, 35, 36 and 37 are inserted in series with the windings and assist in keeping out'the high frequency oscillations.

Having thus described my invention,'its

operation will be apparent. The high frequency oscillations which might otherwise enter the windingsof the machine and discharge to the frame are kept out by the condensers and the inductances, as illustrated.

Having thus described my invention,

what I claim as new, and desire to secure by Letters Patent, is:

transformer and the generator.

2. The combination of a motor, a gen-: erator drlven thereby, an aerial, a local closed oscillatorycircuit including a spark ap, a condeser and an inductance, a transformer for supplylng energy to said local circuit, wire leads leading from the genthe,

erator to said transformer, wire leads supplying current to said motor, said aerial and local circuit .being in' such proximity to and relation with the wiring of said ,generator and motor that high frequency oscillations are producedin said wiring by the wave action of said oscillatory circuit and a plurality of condensers, one terminal of a condenser being connected to the frame of the generator and another terminal to the wire leads. between the generator and transformer,and a plurality of condensers for protecting the motor, one terminal of the condensers being connected to the motor frame, the other terminals'of the condensers being respectively connected to the leads for supplying the motor with current.

3. The combination of an aerial, a local closed oscillatory circuit including a spark ga'p,'a condenser and an inductance, a transformer for supplying energy-to said local circuit, a dynamo, a motor for driving said dynamo,.a switch-board, a rheostat located on said switch-board, wires connecting said rheostat with the armature of said motor, the aerial and local'circuit being adjacent to the wiring of. the generator and a condenser, one plate of said condenser being connected to one of the wires leading from the rheostat and the other plate being connected to the frame'of the motor.

' 4. The combination of an electro-dynamic machine, including a frame, an armature and a field, a switchboard, a rheostat lo-' cated on said switchboard, wires connecting said rheostat with said armature, and a condenser, one plate of said condenser being connectedtooneof said wiresv leading from the rheostat, and the other. plate being connected to the-frame of the machine;

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

ROBERT H; MARRIOTT.

V Witnesses: I

W. 0.. MAncnsoN, D. -HAnoLn BUSH. 

